Material screening includes the use of vibratory screening machines. Vibratory screening machines provide the capability to excite an installed screen such that materials placed upon the screen may be separated to a desired level. Oversized materials are separated from undersized materials. Over time, screens wear and require replacement. As such, screens are designed to be replaceable.
Vibratory screening machines and their replaceable screens have several drawbacks that limit their productivity and use. In vibratory screening machines, the material to be separated is placed on flat or corrugated replaceable screens. The replaceable screens are tensioned over a surface of the vibratory screening machine such that the replaceable screen tightly fits on the machine. A tensioning arrangement is provided with the machine and is used to provide a tensioning force on the screen. Several techniques are used to tension screens on vibratory screening machines. One technique includes the use of special attachment hooks that grip the sides of the screen and pull it onto a surface of the machine. Replaceable screens have a substantially planar screen area and material often builds up at the screen edges causing maintenance and contamination problems.